1. Field of the Invention
The invention relates to a lubricating structure for a speed reducer and, more particularly, to a lubricating structure for a speed reducer, which includes a reduction gear that rotates interlocking with an output shaft of a drive source and that is provided inside a case, guides lubricating oil, which is stored at a bottom inside the case, toward a catch tank by scooping up the lubricating oil with the use of the reduction gear and then supplies the lubricating oil from the catch tank to a lubricating oil supply object, such as a lubricated portion and a cooled portion.
2. Description of Related Art
Because lubricating oil is not supplied to lubricated portions until lubricating oil accumulates in a catch tank, it has taken time to start supplying lubricating oil. Therefore, in order to quickly supply lubricating oil to a lubricating oil supply object, there is known a structure (see, for example, Japanese Patent Application Publication No. 2012-172779 (JP 2012-172779 A)). In the structure, an opening that guides scooped-up lubricating oil to a catch tank is provided at the upper portion of the catch tank, a supply port that supplies lubricating oil from the catch tank to the lubricating oil supply object is provided below the opening, and a guide member that guides lubricating oil from the opening to the supply port is provided between the opening and the supply port. Thus, it is possible to quickly supply lubricating oil to the lubricating oil supply object by guiding lubricating oil to the supply port with the use of the guide member before the oil level of lubricating oil in the catch tank reaches the support port.